Patent GB-358889-A (GB)
Title: Improvements in or relating to electrical signalling systems
IPC: H04L12/18
Filed: 1930-07-09
Abstract: 358,889. Electric signalling systems. ASSOCIATED TELEPHONE & TELEGRAPH CO., 1033, West Van Buren Street, Chicago, U.S.A. July 9, 1930, No. 20814. Convention date, July 15, 1929. [Class 4 (i).] Relates to an electric signalling system for transmitting information regarding the selling price of various stocks so that such prices may be indicated at a plurality of receiving points. Figs. 1 to 8 show the transmitting equipment corresponding to a single operator, further transmitters T2, T3, T4 together with a plurality of receivers and repeaters being shown in Fig. 9. Figs. 10, 11, and 12 show one arrangement of receiving equipment. General operation. The stocks, which are listed by means of one, two or three letters, are transmitted to the receivers, located in the brokers' offices, under the control of the appropriate keys A .. Z, Fig. 1. Transmission of the stocks is dealt with by two operators, those stocks represented by letters A .. K say, whether used alone or as the first letter of a combination being assigned to one operator and the stocks corresponding to letters L .. Z being dealt with similarly by a second set of keys under the control of the second operator. When the keys corresponding to a particular stock are operated, the stock letters are registered on the registers SR1, SR2, SR3, Fig. 2, which operates translators ST1, ST2, ST3, Fig. 3, and through an intermediate distributing frame IDF and registers SH, ST, SU effects the translation of the stock letters into a three digit code. The price of the stocks is transmitted by digit keys DK, Fig. 5, the digits being registered on registers PH, PT, PU, PF, Fig. 7, the latter register dealing with fractional prices. Moreover " range " indications, i.e. yesterday's closing price, highest and lowest prices, last price, &c. are effected by keys RK and registered on register R, Fig. 6. The equipment RS2, Fig. 6, constitutes a duplicate of the registering apparatus, Figs. 4, 6 and 7, and the arrangement is such that the register sets are used alternately in order that a second registration may be effected while the first is held and is being transmitted. Fig. 8 shows the impulse sending equipment, the impulse generating equipment being successively associated with the register sets by relays 809 .. 824. Each digit transmitted to the receivers over the line wire 827 constitutes four impulses of alternate polarity, the strength of the impulses depending upon the setting of the registers. At the remote end of the line the impulses operate polarized and marginal relays 902, 903, 904, Fig. 9, of a repeater R1 from which the impulses are repeated to the several receiving stations. Detailed operation ; stock registration. The digit letters representing the stock are successively stored by corresponding relays in the registers SRI, SR2, SR3 upon the successive operation of the appropriate keys, transfer from register to register being effected by relays 201, 203. Price and "range" registration. The various price digits are recorded in registers PH, PT, PU, PF, Fig. 7, upon operation of the appropriate keys DK, Fig. 5, the relays of the registers being energized singly or in pairs according to the value of the digit. Similarly the " range " of the price as determined by a key in the group RK is recorded in the register R, Fig. 6. Translation of stock letter code. Upon operation of the transfer relay 701 of the register of the first price digit a circuit is closed according to the number of letters registered, for a relay in one of the groups ST1, ST2, ST3 to effect translation of code. In the event of the registration of three letters, the circuit is closed over contacts of operated relays in registers SR3, SR2 for a relay in the group ST3 which closes contacts of a plurality of groups of leads, one group of which is selected by the operated relay in the register SR1 to mark three contacts on the frame IDF appropriate to the stock and which are connected to digit contacts in the numeral groups CD1, CD2, CD3 so as to operate corresponding relays in the numerical registers SH, ST, SU. Upon operation of the next transfer relay 703, the holding circuit of the operated relays in group ST3 and registers Fig. 2, is released ready for the reception of a further coded stock. Cancellation in the event of incorrect registration. If an error in setting up a stock occurs, the registration may be cancelled by operation of a key ER, Fig. 1, which operates relay 613, Fig. 6, to open the holding circuits in the operated register relays. Transfer to register set RS2 and connection of registers to sender, Fig. 8. When transfer relay 610 of the price range register is operated, relay 615 is energized to render the register equipment which is identical with that shown in Figs. 4, 6 and 7 effective for further stock and price registrations while the first registration remains held on the equipment shown in detail and rendered unresponsive to further signals by the switching relays such as 702, 704, &c., Fig. 7, relays 403, 404, 405, Fig. 4. Relay 610 also operates relay 612 which energizes relays 710, 711, 825, 826 for switching the stock and price register marking leads through to the transmitter, Fig. 8. Operation of transmitter, Fig. 8. Operation of relay 612 also earths lead 617 to initiate operation of the sender. Relay 804 is operated over interrupter contacts 803 to energize relay 805 which in turn switches relay 806 into the interrupter circuit. Relay 806 responds to each interruption and effects the transmission of alternate positive and negative impulses over the line 827. Normally weak impulses determined by resistances 801, 802 are transmitted, but according to the marking of the leads A .. D by the stock price and range registers certain impulses may be strengthened. Thus each recorded digit is transmitted as a four-impulse code. The first impulse is negative and is weak or strong according to whether or not the lead A is marked by the A relay of the price register PH. Similarly the nature of the second impulse, which is positive, is determined by the marking of the lead B which is associated with the B relay of the register. Relays 808, 807 are then operated to connect in. circuit the leads C, D and the third and fourth impulses are transmitted in a similar manner the nature of these impulses being determined by relays C, D of register PH. Relays 808, 807 effect operation of transfer relays 809, 810 to connect the leads A .. D to the next set of register relays PT when the cycle of operations of relays 808, 807 is repeated to transmit four impulses characteristic of the setting of register PT. In like manner groups of impulses characteristic of the setting of registers PU, PF, SH, ST, SU and R are then transmitted, transfer of the impulsing equipment to the various registers being effected by relays 809 .. 824. Upon operation of relay 824 impulsing is terminated and the locking circuit of the operated register, switching and transfer relays is opened to cause release. The locking magnet LM for the range keys RK, which prevents setting up of a second complete registration in RS2 before the first quotation is transmitted, is also released. When the range register in RS2 is operated, a circuit is closed for relay 614 through contacts of relay corresponding to relay 610 and relay 614 is operated and relay 615 is released to again bring into circuit the original register equipment in preparation for the next signal. Repeating apparatus, Fig. 9. As previously described the stock quotations are dealt with by two operators, the first operator being provided with transmitter T<1> shown in detail in Figs. 1 to 8 and a spare transmitter T<2> which can be brought into use in the event of faulty operation of transmitter T<1> by key 901. Similarly the second operator who deals with stocks the initial letters of which are L .. Z has two transmitters T<3>, T<4>. The pairs of transmitters are associated with repeaters R<1>, R<2> respectively, each comprising a sensitive negatively polarized relay 902, sensitive non-polarized relay 903 and a marginal relay M connected in series with the line. The repeaters R1, R2 operate pairs of receivers RE1, RE2 (shown in detail); RE3, RE4, &c., arranged in series and in pairs, each receiver of a. pair being associated with one operator. If the indications are to be repeated at a distance further repeaters R3, R4 may be interposed between repeaters R1, R2 and the receivers. The relays 902, 903, 904 respond to the impulses in such a manner that an identical series of impulses is repeated. Receiving apparatus, Figs. 10, 11 and 12. The repeated impulses operate relays 1001, 1002, 1003 of the receiver so as to record the price digits on registers PH, PT, PH, PF. The relays 1001, 1002, 1003 are respectively, negatively and positively polarized and marginal and they respond to the impulses of each digit in such a manner that the digits are successively recorded by operation of relays A .. D, singly, or in pairs, of the registers. Associated with each register is a master switch MS1, MS2, &c. which is set in accordance with the recorded digit. Upon operation of the transfer relay 1012 after registration of the first digit the operation of the master switch MS1 is initiated over contacts of register relays A .. D and the switch is driven into a position characteristic of the digit recorded on the register. The switch is driven by the spring 1050 until the locking magnet 1027 fails to find a circuit over wipers 1021, 1022 and contacts of register relays. The master switches MS2, MS3, MS4 are set in a similar manner into positions characteristic of digits recorded on registers PT, PU, PF. The stock and " range " digits are recorded in a similar manner upon registers SH, ST, SU, R, Fig. 11, the relays of the stock registers however controlling pyramidally arranged contacts directly associated with the indicating apparatus. Selecting st